Keysight Technologies FieldFox Microwave Analyzers

Keysight Technologies FieldFox Microwave Analyzers
Keysight Technologies
FieldFox Microwave Analyzers
4/6/6.5/9/14/18/26.5 GHz
Today, accurate RF and microwave measurements are becoming increasingly necessary in harsh
and hard-to-reach environments. These scenarios span a wide range of conditions: day or night,
rain or shine, hot or cold; aboard a ship, in an aircraft, or in a vehicle.
In these situations, a handheld instrument must be capable of making the required measurements
with sufficient levels of performance and accuracy. Those attributes are important; however, given
the expected operating conditions, physical and environmental specifications are equally important
to the instrument and the user (Figure 1). This white paper presents general suggestions and specific
examples regarding the essential attributes of handheld analyzers that will be used in harsh conditions.
Figure 1. The ideal RF or microwave handheld analyzer must be capable of making accurate measurements in
tough working conditions.
Establishing a reference for “ruggedness”
United States military specification US MIL-PRF-28800F provides a set of benchmarks for test
equipment that will be used in the testing and calibrating of electrical and electronic equipment.
The spec includes four classes that range from the “extremes of world climatic variation” (Class 1)
to controlled, protected operational environments (Class 4).
The 88-page specification is quite detailed, and section 3.8 uses 13 major categories to define the
environmental requirements. Six of these are especially important in handheld analyzers:
– Environmental conditions (3.8.1)
– Temperature and humidity (3.8.2)
– Altitude (3.8.3)
– Vibration (3.8.4)
– Mechanical shock (3.8.5)
– Water resistance (3.8.6)
Within the bounds of these specifications, an instrument that satisfies Class 2 requirements will be
capable of operating in rugged operational environments that include unprotected, uncontrolled
climatic conditions. These are high hurdles for handheld RF and microwave instruments.
Another important consideration for handheld analyzers is operation in potentially explosive conditions. One of the key benchmarks is MIL-STD-810G, which covers the environmental considerations
a device may experience in its service life and provides relevant laboratory tests. Within the standard,
Test Method 511.5 deals with operation in an explosive atmosphere. Testing typically includes operation of the unit-under-test (UUT) in a chamber filled with explosive gases that may ignite if the UUT
produces a spark. Passing this test is especially important for handheld instruments that may be used
near the flammable fuels or gases present around aircraft, vehicles, mining operations, and so on.
Drawing a line in the sand
As demonstrated by currently available RF and microwave instruments, there are two ways to create
a handheld unit: one is to repackage a conventional benchtop analyzer, and the other is to create an
all-new instrument designed with field use firmly in mind.
Using MIL-PRF-28800F as a yardstick, many of today’s “repackaged” instruments fall short in several
key areas: temperature and humidity, vibration, mechanical shock, water resistance and dust exposure. Most stumble due to poor choices in areas such as component selection and package design.
For example, components designed to work in an AC-powered device tend to be power-hungry, which
has two undesirable consequences. One is shorter battery life, which is a significant shortcoming in
the absence of AC outlets or spare batteries. The other is heat: these components often need
fan-based cooling, and this requires vents to provide airflow through the instrument enclosure.
With these attributes, a typical repackaged design will have a hard time operating in tough—but
typical—conditions: rain, dust, humidity, fluctuating temperatures, and so on. As a worst-case
example, imagine a day in the desert, working on satellite ground stations with a fan-cooled handheld. Sandstorms are common and the instrument is likely to ingest significant amounts of foreign
matter, which can lead to overheating more quickly than when operating in ideal conditions.
Designing from the ground up
The alternative to a repurposed instrument is a purpose-built device. In the ideal case, industrial and
electronic designers would have the freedom to start with a clean slate. Design choices would be
shaped by the need to provide high quality RF and microwave measurements in difficult conditions.
To reduce the amount of equipment to be carried into the field, the overall design would be flexible
enough to provide a wealth of capabilities in a compact package: cable and antenna analysis, vector
network analysis, spectrum analysis, power measurement, interference analysis, and vector voltage
measurement (Figure 2).
Figure 2. This handheld analyzer was purpose-built to meet the needs of personnel who need to make a variety of
precise, on-the-go measurements.
Creating a field-worthy industrial design
To get a firsthand perspective, a Keysight Technologies, Inc. design team left the office behind and
tagged along with technicians and engineers in the field. As the field personnel performed routine
maintenance, in-depth troubleshooting, and everything in between, members of the Keysight design
team were there—observing, asking questions and listening.
The team traveled to a variety of worksites in vans, pickups and trucks. The “good” instruments
usually rode up front with the crew; the other gear was often tossed—sometimes literally—into the
cargo area of a van or the bed of a pickup. In all cases, the people, vehicles and instruments had to
be equipped for a wide range of conditions, day or night, rain or shine.
Those experiences translated into attributes that make a handheld analyzer ready for the toughest
conditions. For example, a completely sealed enclosure that is compliant with US MIL-PRF-28800F
Class 2 requirements will ensure durability in harsh environments. Consistent with the spec, a waterresistant chassis, keypad and case let the instrument withstand salty, humid environments. Gasketsealed doors will protect instrument interfaces from moisture, and a dust-free design—with no vents
or fans in the case—will help extend instrument availability and reliability.
The package should also withstand shock and vibration, and the connector bay should be designed
to protect the RF connectors from damage due to drops or other external impacts. Two additional
attributes will help a unit survive drops onto all six faces. One is a case with a curved bottom and
rounded corners: These disperse impact and increase structural resistance to shock and impact from
all angles. Another useful attribute is the polymer blend used in the case: In addition to its innate
durability, the polymer can be formulated to resist shattering at the lowest temperature of the desired
operating range.
Designing from the ground up (continued)
Defining field-ready ergonomics
Time spent in the field made indelible impressions that led to practical, meaningful decisions about
ergonomics. For example, a nonslip rubber grip—built into the case—that fits securely into the user’s
hands can also be designed to prevent the analyzer from sliding off the hood of a vehicle.
A vertical or “portrait” orientation would make an instrument easy to hold. Coupling that with a carefully designed keypad layout will make it easy for a user to operate the instrument with their thumbs
(Figure 3). Also, a weight of about 3.0 kg (about 6.6 lbs) is relatively easy to carry for extended
periods in the field.
Because the instrument may be used day or night, inside or outside, the user will benefit from a
bright, low-reflective display and multiple display modes that optimize viewing under a wide range of
lighting conditions. In addition, backlit keys will enable operation in darkness.
Figure 3. A portrait orientation coupled with sufficiently large front-panel buttons enables easy operation,
even when wearing gloves.
Reducing power consumption
The electronic design of a handheld analyzer requires a delicate—and complex—balance between
performance, power consumption, heat, and battery life. For FieldFox, in-house scientists modified existing high-performance chips and technologies to retain performance while reducing power
consumption. The result: an analyzer that draws about 14 W and lasts 3.5 hours on a single charge.
Because the electronics consume just 14 W of power, the enclosure can be completely sealed. The
power-efficient design has another benefit: the instrument provides fully specified performance over
an operating temperature range of 14 to 131 °F (-10 to +55 °C).
Leveraging benchtop capabilities
For the Keysight team, the next step was to pack the required levels of performance and capability
into a rugged, ergonomic design that met the criteria described above. As a starting point, they
borrowed capabilities from Keysight’s benchtop analyzers, many of which are today’s best
microwave instruments.
For network analysis, the designers leveraged built-in calibration hardware and highly accurate
calibration algorithms from high-end vector network analyzers (VNAs) to enable precise, repeatable
measurements. With an emphasis on portability, the designers simplified calibration by adding built-in
standards, a choice that enables measurements in the field without additional accessories. With most
other instruments, the addition of devices such as jumper cables to the test port requires recalibration
using an external calibration kit that must be carried into the field.
To enhance spectrum analysis, the design team leveraged the power measurements used in Keysight
benchtop signal analyzers. This enables fast, accurate one-button power measurements of channelized communication systems. For improved accuracy, the designers created an internal amplitude
alignment function that operates automatically as environmental conditions change. This provides
amplitude accuracy of ±0.5 dB with no warm up required across an operating temperature range
of 14 to 131 °F.
Covering more ground
The results of the design process are embodied in the Keysight FieldFox handheld analyzers. Inside
and out, the FieldFox family was designed with on-the-go applications—and end users—firmly in
mind (Figure 4). Within its compact package, a FieldFox analyzer can be configured as a cable and
antenna tester (CAT), spectrum analyzer or vector network analyzer. Additional capabilities include
a power meter, a vector voltmeter, an independent signal source, a variable DC supply, a frequency
counter, an interference analyzer, and built-in GPS. The FieldFox family consists of 16 models, with
top-end frequencies of 4, 6 and 6.5 GHz in the RF models and 9, 14, 18 and 26.5 GHz in the
microwave models.
This level of flexibility can replace a variety of instruments. It also enables a user to define a “just
right” initial configuration and, later on, easily amend it with additional capabilities as needs change
and budgets allow. Because those capabilities are inclusive, a CAT version can be enhanced with
any of the other capabilities—spectrum analysis, network analysis, etc.—by simply acquiring and
applying a license key. No additional hardware is required, nor is a return to the factory.
As a final point, the product warranty is an important consideration for any instrument that will be
used in the field. While most instruments have a one-year warranty, FieldFox handheld analyzers
carry the added confidence of a three-year warranty.
Figure 4. The versatile FieldFox handheld analyzers
help reduce equipment costs while enhancing
convenience and efficiency.
Measuring up in the field
It’s one thing to provide handheld microwave measurements that agree with those
made using a benchtop analyzer. It’s quite another to put those capabilities into an
analyzer that measures up against US MIL-PRF-28800F Class 2 requirements and
has been type-tested to meet the MIL-STD-810G test for operation in explosive
environments. With a unique combination of advanced measurement capabilities and
a durable package, the FieldFox handheld analyzers are equipped to handle routine
maintenance, in-depth troubleshooting, and more—virtually anywhere technicians
and engineers need to go.
Related literature
FieldFox Handheld Analyzers, Brochure
FieldFox Combination Analyzers, Technical Overview
FieldFox Microwave Spectrum Analyzers, Technical Overview
FieldFox Microwave Vector Network Analyzers, Technical Overview
FieldFox Handheld Analyzers, Data Sheet
FieldFox Handheld Analyzer, Configuration Guide
FieldFox N9912A RF Analyzer, Technical Overview
FieldFox N9912A RF Analyzer, Data Sheet
FieldFox N9923A RF Vector Network Analyzer, Technical Overview
FieldFox N9923A RF Vector Network Analyzer, Data Sheet
Download application notes, watch videos, and learn more:
08 | Keysight | FieldFox Microwave Analyzers 4/6/6.5/9/14/18/26.5 GHz - Brochure
A personalized view into the information most relevant to you.
Three-Year Warranty
Keysight’s commitment to superior product quality and lower total cost
of ownership. The only test and measurement company with three-year
warranty standard on all instruments, worldwide.
Keysight Assurance Plans
Up to five years of protection and no budgetary surprises to ensure your
instruments are operating to specification so you can rely on accurate
Keysight Technologies, Inc.
DEKRA Certified ISO 9001:2008
Quality Management System
Keysight Channel Partners
Get the best of both worlds: Keysight’s measurement expertise and product
breadth, combined with channel partner convenience.
For more information on Keysight
Technologies’ products, applications or
services, please contact your local Keysight
office. The complete list is available at:
United States
(877) 894 4414
55 11 3351 7010
001 800 254 2440
(800) 829 4444
Asia Pacific
Hong Kong
Other AP Countries
1 800 629 485
800 810 0189
800 938 693
1 800 112 929
0120 (421) 345
080 769 0800
1 800 888 848
1 800 375 8100
0800 047 866
(65) 6375 8100
Europe & Middle East
United Kingdom
0800 001122
0800 58580
0800 523252
0805 980333
0800 6270999
1800 832700
1 809 343051
800 599100
+32 800 58580
0800 0233200
8800 5009286
0800 000154
0200 882255
0800 805353
Opt. 1 (DE)
Opt. 2 (FR)
Opt. 3 (IT)
0800 0260637
For other unlisted countries:
This information is subject to change without notice.
© Keysight Technologies, 2012 - 2014
Published in USA, August 2, 2014
Was this manual useful for you? yes no
Thank you for your participation!

* Your assessment is very important for improving the work of artificial intelligence, which forms the content of this project

Download PDF